8) Find \( f^{\prime}(x) \) using the limit definition of the denivative Then evaluate at \( x=-2 \). \[ f(x)=-6 x^{2}-3 x+2 \]
Solución de inteligencia artificial de Upstudy
Responder
Solución
Respondido por UpStudy AI y revisado por un tutor profesional


Extra Insights
To find \( f^{\prime}(x) \) using the limit definition of the derivative, we start with the formula: \[ f^{\prime}(x) = \lim_{h \to 0} \frac{f(x + h) - f(x)}{h} \] For our function \( f(x) = -6x^2 - 3x + 2 \), we first compute \( f(x + h) \): \[ f(x + h) = -6(x + h)^2 - 3(x + h) + 2 \] Expanding \( f(x + h) \): \[ = -6(x^2 + 2xh + h^2) - 3x - 3h + 2 = -6x^2 - 12xh - 6h^2 - 3x - 3h + 2 \] Now, we find \( f(x + h) - f(x) \): \[ f(x + h) - f(x) = (-6x^2 - 12xh - 6h^2 - 3x - 3h + 2) - (-6x^2 - 3x + 2) = -12xh - 6h^2 - 3h \] Next, we substitute this back into the limit definition: \[ f^{\prime}(x) = \lim_{h \to 0} \frac{-12xh - 6h^2 - 3h}{h} = \lim_{h \to 0} (-12x - 6h - 3) \] As \( h \) approaches 0, the limit simplifies to: \[ f^{\prime}(x) = -12x - 3 \] Now, we evaluate at \( x = -2 \): \[ f^{\prime}(-2) = -12(-2) - 3 = 24 - 3 = 21 \] Thus, \( f^{\prime}(-2) = 21 \).
